vacuum solenoid for lights

[graham]

Tried out the lights and with motor running and light switch off the light pods go down ,but when operate the light switch the lights only come up about 2/3rds and lights are on .
When no vacuum the pods do come up fully.
Have I connected the pipes to the vac unit and the motor the wrong way around or is it likely to be something else?

Graham

[bob_rich]

Hi Graham

Looking at the picture you have the fail safe type vacuum relay assembly so I assume you have a single operating vacuum unit. If the light pods come up with the motor running but not with the motor off suspect that the suck of the vacuum is leaking through the valve. with the motor running the constant vacuum suck leaking through the valve may provide sufficient force to balance the force of the return springs.

I notice U have use thin wall clear plastic pipe for the vacuum valve connections. I think thicker wall tubing may be a better choice to prevent the tube collapsing under the vacuum suck especially at bends and when hot.

It took me 3 months of fiddling 2 get mine to work!!

best of luck

Bob

[GrUmPyBoDgEr]

A bit difficult to judge from your photo but it seems that you have a solenoid valve that switches the vacuum on when switched on but when switched off it has no way to release the vacuum to atmosphere.
If that is so then that is where your problem lies.
I think you will need another type of solenoid valve that will also release the vacuum

Cheers
John

[graham]

Thanks Bob and John - I took the valve apart and looked inside -worked out that the vac from the manifold goes to term 1 and to the pod terminal 2. Hey presto they work !!!

[graham]

Just a note the clear tube was sold as a vacuum tube so we will see how it performs.

[GrUmPyBoDgEr]

Having not seen a vacuum selenoid like that before I was guessing in the dark.
From yours & Bob's comments am I correct in assuming that the valve shown in your photo is in fact a standard +2 vacuum solenoid?

I'll try & figure out for myself where on that valve the vacuum is released to atmosphere because your problem is resolved & there's no point in continuing a discussion on hypothesis

Cheers
John

[Galwaylotus]

I notice U have use thin wall clear plastic pipe for the vacuum valve connections. I think thicker wall tubing may be a better choice to prevent the tube collapsing under the vacuum suck especially at bends and when hot.

It took me 3 months of fiddling 2 get mine to work!!

I installed fuel hose for the vacuum circuit. Well reinforced and thick walled too. Holds up well in a hot oily environment (what leaks? ) Works well.

[bob_rich]

Hi again

John commented in his post if the valve in question is a standard +2 one. Mine looks like the one in the picture and in the Lotus service manual although it is a line drawing it does show an arrangement very much like the photo and is like the valve in my December 1973 +2 S 130. The vacuum should be released by some small drilling just under the solenoid assembly.

Hope this helps

Bob